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1.
Chem Biol Interact ; 311: 108794, 2019 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-31421115

RESUMO

Acanthoic acid (AA) is a pimaradiene diterpene isolated from Acanthopanax koreanum Nakai (Araliaceae), with anti-inflammatory and hepatic-protective effects. The present study intended to reveal the effect and mechanism of AA on nonalcoholic fatty liver disease (NAFLD) associated with lipid accumulation by activating Farnesoid X receptor (FXR) and liver X receptors (LXRs) signaling. C57BL/6 mice were received a modified Lieber-DeCarli diet with 71% high-fat (L-D) and treated with AA (20 and 40 mg/kg) or equal volume of saline for 12 weeks. The regulation of AA on lipid accumulation was also detected in pro-steatotic stimulated AML12 cells with palmitic acid (PA). When L-D diet-fed mice were treated with AA, loss in body weight, liver index, and liver lipid droplet were observed along with reduced triglyceride (TG) and serum transaminase. Furthermore, AA decreased sterol regulatory element binding protein 1 (SREBP-1) and target genes expression, regulated PPARα and PPARγ expressions, ameliorated hepatic fibrosis markers, enhanced hepatic FXR and LXR, and regulated AMPK-LKB1 and SIRT1 signaling pathway. Moreover, AA attenuated lipid accumulation via FXR and LXR activation in steatotic AML-12 cells, which was confirmed by guggulsterones (FXR antagonist) or GW3965 (LXR agonist). Activation of FXR and LXR signaling caused by AA might increase AMPK-SIRT1 signaling and then contribute to modulating lipid accumulation and fatty acid synthesis, which suggested that activated FXR-LXR axis by AA represented an effective strategy for relieving NAFLD.


Assuntos
Diterpenos/farmacologia , Lipogênese/efeitos dos fármacos , Receptores X do Fígado/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal/efeitos dos fármacos , Linhagem Celular , Dieta Hiperlipídica , Diterpenos/química , Regulação da Expressão Gênica/efeitos dos fármacos , Receptores X do Fígado/agonistas , Receptores X do Fígado/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , PPAR alfa/genética , PPAR alfa/metabolismo , Ácido Palmítico/farmacologia , Receptores Citoplasmáticos e Nucleares/antagonistas & inibidores , Receptores Citoplasmáticos e Nucleares/genética , Transdução de Sinais/efeitos dos fármacos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Triglicerídeos/sangue
2.
Anal Chim Acta ; 1049: 188-195, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30612650

RESUMO

An electrochemical immunosensor for ultrasensitive detection of acrylamide (AA) in water and food samples was developed. SnO2-SiC hollow sphere nanochains with high surface area and gold nanoparticles with good electroconductivity were fabricated onto the surface of a glassy carbon electrode pre-coated with chitosan. The coating antigen (AA-4-mercaptophenylacetic acid-ovalbumin conjugate, AA-4-MPA-OVA) was immobilized on the electrode. Polyclonal antibody specific for AA-4-MPA was conjugated to gold nanorod (AuNR) as primary antibody (AuNR-Ab1). Horseradish peroxidase labelled anti-rabbit antibody produced in goat was conjugated to AuNR as secondary antibody (HRP-AuNR-Ab2). For detection, the analyte (AA-4-MPA) in sample competed with coating antigen for binding with AuNR-Ab1. After washing, HRP-AuNR-Ab2 was added to capture the AuNR-Ab1, and the electrical signal was obtained by addition of hydroquinone and H2O2. After investigation of the binding ability on nanomaterials and optimization of competitive immunoassay conditions, the proposed immunosensor exhibited a sensitive response to AA with a detection limit of 45.9 ±â€¯2.7 ng kg-1, and working range of 187 ±â€¯12.3 ng kg-1 to 104 ±â€¯8.2 µg kg-1 for drinking water samples. Recoveries of AA from spiked samples were ranged from 86.0% to 115.0%. The specificity, repeatability and stability of the immunosensor were also proved to be acceptable, indicating its potential application in AA monitoring.


Assuntos
Acrilamida/análise , Técnicas Eletroquímicas/métodos , Imunoensaio/métodos , Nanotubos/química , Acrilamida/imunologia , Anticorpos/imunologia , Técnicas Biossensoriais/métodos , Compostos Inorgânicos de Carbono/química , Quitosana/química , Café/química , Água Potável/análise , Contaminação de Alimentos/análise , Ouro/química , Limite de Detecção , Ovalbumina/imunologia , Fenilacetatos/imunologia , Compostos de Silício/química , Solanum tuberosum/química , Compostos de Sulfidrila/imunologia , Compostos de Estanho/química
3.
Biosens Bioelectron ; 98: 305-309, 2017 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-28697442

RESUMO

Histamine (HA) is a biogenic amine that can accumulate to high concentration levels in food as a result of microbial activity and can cause toxic effects in consumers. In this work, a portable electrochemical immunosensor capable of detecting HA with high sensitivity and selectivity was developed. Prussian blue-chitosan-gold nanoparticle (PB-CS-AuNP) nanocomposite films with excellent biocompatibility were synthesized and characterized by scanning electron microscopy and energy dispersive X-ray analysis. The PB-CS-AuNP were coated onto a screen-printed electrode by one-step electrodeposition and used to conjugate the HA ovalbumin conjugate (HA-Ag). HA was determined by a competition between the coating HA-Ag and the HRP labeled HA antibody (HRP-HA-Ab). After careful optimization of assay conditions and Box-Behnken analysis, the developed immunosensor showed a linear range from 0.01 to 100µg/mL for HA in fish samples. The average recoveries from spiked samples ranged from 97.25% to 105%. The biosensor also showed good specificity, reproducibility, and stability, indicating its potential application in monitoring HA in a simple and low cost manner.


Assuntos
Técnicas Biossensoriais/métodos , Histamina/isolamento & purificação , Nanopartículas Metálicas/química , Quitosana/química , Técnicas Eletroquímicas/métodos , Ouro/química , Histamina/química , Imunoensaio/métodos , Nanocompostos/química , Nanotubos de Carbono/química
4.
Talanta ; 170: 502-508, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28501203

RESUMO

Progesterone (P4) is a kind of hormone that can cause neuropathic disturbances in humans when the concentration overpasses a certain degree. In this work, an electrochemical immunosensor capable of detecting P4 sensitively and selectively was developed. Thionine-graphene oxide (Thi-GO) composites with excellent biocompatibility were synthesized and coated to a clear glassy carbon electrode. P4 coating antigen (P4-OVA) was immobilized to the electrode, then sample as well as biotinylated antibody (biotin-P4 Ab) were added. The free P4 can compete with P4-OVA for binding to biotin-P4 Ab. After the further addition of streptavidin-HRP, H2O2 was introduced to develop electrical signal for quantitative determination of P4. After careful optimization of assay conditions, the proposed immunosensor showed a linear range from 0.02 to 20ngmL-1 for P4 in milk samples. The averaged recoveries from spiked samples ranged from 84.0% to 102.0%, which correlated well with standard HPLC-MS/MS. The biosensor also showed good specificity, reproducibility and stability, indicating its potential application in monitoring of P4 in a simple and low cost manner.


Assuntos
Técnicas Biossensoriais/métodos , Biotina/química , Grafite/química , Leite/química , Fenotiazinas/química , Progesterona/análise , Estreptavidina/química , Animais , Análise de Alimentos/métodos , Imunoensaio/métodos , Imunoconjugados/química , Limite de Detecção , Reprodutibilidade dos Testes
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